VDB from Polygons: non-watertight geos?

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Hi!

I'm converting an asset to VDB but some geos have no thickness (non-watertight). I remember seing some node/option to deal with those geos. It would give it thickness in a smart way... Know anything about this?

-Olivier
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I always start with a polyextrude and add a small width. Sometimes it is easier just to model a watertight likeness to supply as a collider.
Using Houdini Indie 20.0
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Geo seal by momme is a valid option:
https://momme.gumroad.com/l/geoseal?layout=profile [momme.gumroad.com]
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CYTE
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Another option might be Tet Embed followed by a VDB From Polygons.

EDIT: And also turn off Enlarge Input Mesh on the Tet Embed
Edited by edward - March 13, 2024 17:04:23
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Or use Tet Conform instead of Tet Embed.
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Vdb topology SDF will reconstruct the data, but it will be larger in size.
The trick is to appply a reshape SDF and erode 1-1.5, convert VDB to poly and us negative ISO offset values.
then you can do another VDB from polygons, from a nice watertight piece of geo, this setup of steps will get you
very close to the original source mesh.
I'm not lying, I'm writing fiction with my mouth.
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Alright, thanks for all the info! I'll do some tests.

Olivier
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In production, we get open surfaces from Modeling often. The common practice is to convert the mesh to an unsigned distance field prior to converting to a signed distance field.


I have an example in the Houdini example file https://www.openvdb.org/download/ [www.openvdb.org] Look for /obj/example_levelset/extruded_sdf
Edited by jbudsberg - April 10, 2024 13:02:11

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